The present disclosure relates to a mattress for subsea pipelines. More specifically, in certain embodiments the present disclosure relates to a pipe-clamping mattress for subsea pipelines and associated methods and system.
In the production of oil and gas from subsea hydrocarbon formations, pipelines are often used to transport the oil and gas along the seafloor. These pipelines can extend over large distances. During production, these pipelines may have a tendency to move or “walk” due to thermal expansion and contraction of the pipelines. This movement of the pipeline can cause many problems, especially at connection points where the pipeline connects to subsea equipment, including pipeline end termination facilities, pumps, and manifolds.
Several methods and devices have been proposed to mitigate the effects of pipeline walking. These methods include the use of rock-dumps and the use of pipeline mattresses to secure the pipeline in place. However, these solutions may not always be optimal. Rock-dumps and conventional mattresses have a tendency of driving a subsea pipeline into soft seafloors when they are installed. As the pipeline works its way into the seafloor, the ability of the rock-dump or conventional mattress to restrict the movement of the pipeline is reduced. Additionally, conventional mattresses also have a tendency of arching over pipelines, reducing their ability to hold down a pipeline.
It is desirable to develop a subsea pipeline mattress capable of restraining a subsea pipeline against axial movements without driving the subsea pipeline into the seafloor.